Statistical Analysis: Confidence Intervals & Hypothesis Testing in City Survey, Exams of Statistics

Download Statistical Analysis: Confidence Intervals & Hypothesis Testing in City Survey and more Exams Statistics in PDF only on Docsity! Math 1530 Name_________________ Review of Confidence Intervals and Test of Hypotheses for proportions All the questions refer to the following story Please read the story carefully A certain organization wants to know the opinion of the adult residents, 35 years of age or older, of the 'XXX' City with a total population of 55,000 (similar size of Johnson City) about lowering the drinking age to 18. Specifically they want to know what proportion of those adults favor lowering the drinking age to 18.They organize a survey and select a simple random sample of 200 adult residents (35 years of age or older) and ask them "Do you think that the drinking age should be reduced to 18?" . In the sample, 140 people answered "yes". 1. What is the population of interest in this case? A. The people that belong to the organization B. All 18 year old people in XXX City C. The 55,000 people in the city D. All adult residents (35 years and older) of the XXX City E. The 200 adults interviewed 2. What is the parameter to be estimated A. 140 B. 0.7 C. 18 D. The proportion of adults (35 years or older) in the city that favor lowering the drinking age to 18 E. All adults (35 years or older) in the city. 3. Based on the sample collected, what is the value of the statistic that you are using to estimate the value of the parameter? A. 140 B. 200 C. 0.7 D. 0.3 E. 18 4. In other places the proportion of the adult population that favor lowering the drinking age to 18 is 0.6 but we think that in XXX City that proportion is higher. How would you write the null and the alternative hypothesis in order to perform a test? A. Ho: p̂ =0.6 Ha: p̂ >0.6 B. Ho: p=0.6 Ha: p>0.6 C. Ho: u=0.6 Ha: u>0.6 D. Ho: p=0.6 Ha: p<0.6 E. Ho: p=0.7 Ha: p>0.7